Pathological gambling is recognized to be a disorder of impulse control. Evidence suggests that a significant proportion of the drug abusing population may be pathological gamblers, and that rates of pathological gambling are 6 to 10 times higher among drug abusers than for the general population. Despite the suggestion in the literature that for the drug abuser enrolled in drug treatment pathological gambling may accompany and reinforce continued drug dependence, interfere with treatment engagement, and be a factor in relapse, not published research has documented the prevalence of pathological gambling among drug abusers enrolled in methadone maintenance treatment, or examined the link between pathological gambling and drug abuse for this population. This proposed Small Grant Research study will establish the prevalence of pathological gambling in a sample of 500 patients from two methadone maintenance treatment programs located in New York City. The correlates of pathological gambling, and the extent to which and reasons why patients gamble while using drugs, use drugs while gambling, and engage in crime in order to obtain money for gambling will also be determined. Respondents will be administered the South Oaks Gambling Screen, a validated, reliable instrument that offers a convenient means for screening populations of drug abusers, as well as general populations, for pathological gambling. The proposed study is conceived of as a building block for an anticipated follow-up study in which in-depth interviews would be conducted with patients from the proposed study who are found to be potential or probable pathological gamblers. These interviews would be designed to generate detailed quantitative and qualitative data to explicate the interconnections between pathological gambling, drug abuse, and crime. The data from these two studies will provide valuable information concerning the role of pathological gambling as a confounding factor that interferes with treatment and rehabilitation. This information will help us identify the critical components of an effective treatment program for drug abusers in methadone treatment who are pathological gamblers.